Auditory processing disorder (also known as central auditory processing disorder or CAPD) is a condition that makes it hard for kids to recognize subtle differences between sounds in words. It affects their ability to process what other people are saying.
Gallium is a solid metal at room temperature, but it melts in your hands. 00:09. When gallium is in its liquid state, if feels like cold melted solder in your hands. 00:33. Melting gallium onto aluminum makes the aluminum brittle enough to break with your fingers.
But in melt treatment technologies they are probably the number one. Although copper is the metal that is longest used technologically by mankind and aluminum one of the shortest, in both industries a variety of melt treatments and sometimes similar technologies were investigated over time.